Use the platform-independent way of calling a script from the shell: "python prog.py", not "prog.py"
Found by Micheal Wells on docs@.
diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst
index 5d4ca96..0b18c6d 100644
--- a/Doc/library/argparse.rst
+++ b/Doc/library/argparse.rst
@@ -46,7 +46,7 @@
Assuming the Python code above is saved into a file called ``prog.py``, it can
be run at the command line and provides useful help messages::
- $ prog.py -h
+ $ python prog.py -h
usage: prog.py [-h] [--sum] N [N ...]
Process some integers.
@@ -61,15 +61,15 @@
When run with the appropriate arguments, it prints either the sum or the max of
the command-line integers::
- $ prog.py 1 2 3 4
+ $ python prog.py 1 2 3 4
4
- $ prog.py 1 2 3 4 --sum
+ $ python prog.py 1 2 3 4 --sum
10
If invalid arguments are passed in, it will issue an error::
- $ prog.py a b c
+ $ python prog.py a b c
usage: prog.py [-h] [--sum] N [N ...]
prog.py: error: argument N: invalid int value: 'a'